Water heating system for faucets

ABSTRACT

An electric water heater is disposed close to a faucet to readily provide heated water to the faucet. This heater provides heated water without the wait required to obtain hot water from the main, remotely-located, hot water heater such as a hot water tank. The electric hot water heater includes a heater tube disposed in contact with an electric resistance heater. The electric resistance heater does not directly contact the water in the heater tube. The electric resistance heater heats the sidewall of the heater tube which, in turn, heats the water in the heater tube. Two layers of insulation are disposed over the electric resistance heater. The heater tube is placed in line with the regular hot water supply pipe.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application No. 62/753,704 filed Oct. 31, 2018; the disclosures of which are incorporated herein by reference.

BACKGROUND OF THE DISCLOSURE 1. Technical Field

This disclosure generally relates to systems that provide hot water to faucets from a location close to the faucet to eliminate the wait for hot water delivered from a remote hot water heater. More particularly, the disclosure relates to an electric hot water heater wherein the heating element is not in direct contact with the water.

2. Background Information

Most hot water in the United States is provided by hot water heaters that include a tank of water and a heating element. A relatively large volume of water such as 40, 60, or 80 gallons is held in a heated tank. The hot water is delivered through a hot water pipe when a user opens a hot water faucet. A drawback with these systems is that the volume of water in the hot water pipe between the faucet and the tank cools down to room temperature in between relatively long uses of the hot water. As such, the user does not receive hot water immediately after opening the faucet. All of the cooler water is pushed out of the faucet before the hot water from the tank is delivered to the faucet. The length of time before the hot water reaches the faucet is mostly determined by the length of pipe between the faucet and the hot water tank. Users who want the hot water usually wait until it is delivered which results in the cooler water being wasted as well as the user being frustrated.

SUMMARY OF THE DISCLOSURE

The disclosure provides a hot water delivery system wherein the hot water pipe near a faucet is heated to maintain a supply of hot water which can be almost immediately delivered by the faucet. The hot water is created by providing a heater that is used with at least a final portion of hot water delivery pipe or a portion of hot water delivery pipe spaced from but close to the faucet. The heater maintains the water within the pipe at a temperature of 80 to 100 degrees Fahrenheit. An exemplary heater is an electric resistance heater with one or more heating elements disposed along with the length of the pipe. The heating element is not in direct contact with the water. Insulation can be used to maintain the heated water. The electric heater can be plugged in to a standard outlet or hardwired to a source of electricity. The heater can have an on/off switch and a thermostat allowing the user to control its operation. Other types of heaters can be used.

In one exemplary configuration, only the final portion of the hot water pipe before the faucet is heated. In another exemplary configuration, the entire run of pipe from the faucet to the hot water tank is heated. In a further exemplary configuration, the heating elements are spaced along the length of the hot water pipe and these can be individually controlled.

Another exemplary configuration provides an electric water heater that is used close to the faucet to provide heated water to the faucet. This heater provides heated water without the wait required to obtain hot water from the main, remotely-located, hot water heater. In this exemplary configuration, the electric hot water heater includes a heater tube wrapped with an electric resistance heater. The electric resistance heater does not directly contact the water in the heater tube. The electric resistance heater heats the sidewall of the heater tube which, in turn, heats the water in the heater tube. Two layers of insulation are disposed over the electric resistance heater. The heater tube is placed in line with the regular hot water supply pipe.

Another configuration uses a bypass water tube provided to direct water from the regular hot water supply pipe around the heater tube such that the hot water from the heater tube is mixed with the cooler water from the regular hot water supply line when the faucet is initially opened in order to cool the temperature of the water delivered and to increase the amount of time the local supply of heated water is delivered.

Another configuration uses a flow restrictor to limit the flow rate of the hot water from the heater tube.

The preceding non-limiting aspects of the disclosure, as well as others, are more particularly described below. A more complete understanding of the devices, systems, and methods can be obtained by reference to the accompanying drawings, which are not intended to indicate relative size and dimensions of the assemblies. In those drawings and the description below, like numeric designations refer to components of like function. Specific terms used in that description are intended to refer only to the particular structure of the embodiments selected for illustration in the drawings, and are not intended to define or limit the scope of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a sink with a water faucet connected to a regular hot water supply pipe that extends from a remote hot water heater wherein electric heaters heat different portions of the regular hot water supply pipe between the hot water heater and the faucet.

FIG. 2 is a front elevation view, with elements partially broken away, depicting a configuration of an electric hot water heater that can be installed close to a faucet to provide fast access to heated water.

FIG. 3 is a section view of the electric hot water heater of FIG. 2.

FIG. 4 is an exploded view of an alternative configuration of an electric hot water heater that can be installed close to a faucet to provide fast access to heated water.

DESCRIPTION OF THE DISCLOSURE

A first exemplary configuration of a hot water delivery system is depicted in FIG. 1. This exemplary system includes a remote hot water heater tank 12 that receives cold water from a water supply pipe 14 and uses a heating element to heat the water in the heater 12 to a desired hot water temperature. Hot water heater tank 12 is connected to one or more faucets 16 with a regular hot water supply pipe 18. In the context of this application, all hot water outlets are referred to as faucets whether they are used as sink faucets, shower faucets, shower heads, or inputs to appliances such as a dishwasher. Although hot water pipe 18 is connected to and supplied with the heated water from hot water heater 12, the supply is not constantly refreshed and the water between heater 12 and faucet 16 can sit at rest for hours between uses. This water cools to room temperature and, unfortunately, is the water which is initially delivered from faucet 16 when the user opens faucet 16. The systems of the disclosure provide a supply of heated water that is readily delivered (for example, delivered within a maximum of fifteen seconds but usually within five seconds after the hot water faucet is opened). A person can open the faucet and use the local supply of heated water and then close the faucet. In this configuration, the cooler water from pipe 18 is delivered after the initial supply of local heated water is delivered. In another configuration, the local heated water is mixed with the supply of cooled water from hot water pipe 18 and delivered until the hot water from hot water heater tank 12 is delivered to faucet 16.

In the first configuration of FIG. 1, at least one pipe heater 20 is connected to at least one portion of hot water pipe 18. Heater 20 maintains the water within the pipe near faucet 16 at a heated temperature (the local supply of heated water) so that the user readily receives heated water after opening faucet 16. Heater 20 is disposed close enough to faucet to deliver the local heated water within fifteen seconds but usually within five seconds. To deliver the local supply of heated water within these times, heater 20 should be located generally within one to ten feet of faucet 16, although the specific pipe diameter and water pressure can alter these limits. Heater 20 maintains the water between 80 and 150 degrees Fahrenheit. In one example, heater 20 is a fifteen inch long resistant electric heating wire that is wrapped around or disposed along a portion of pipe 18. Heater 20 can include a thermostat, an on/off switch, and can be plugged into an outlet or hardwired into the electrical system of the building. Heater can be electric and powered at 110V or 220V.

Heater 20 or a plurality of heaters 20 can be disposed along the entire length of pipe 18 or spaced portions of pipe 18. Locating heater 20 close to faucet 16 allows the heated water to be delivered to the user quickly. Heater 20 can be wrapped around pipe 18 in a coil wrap or bent along the longitudinal axis of pipe 18. Each heater 20 can be wrapped in insulation.

Another exemplary configuration of the water heater used with the system is depicted in FIGS. 2 and 3. Heater 100 includes a bypass mixing supply tube 120 that combines water (initially cooled water) from hot water supply pipe 18 with the local supply of heated water to deliver to the user warmed water while waiting for the hot water to reach faucet 16 from hot water heater tank 12. This is achieved by mixing the room temperature water from pipe 18 with the local supply of heated water in heater 100 using bypass tube 120 and metering the mixture to allow water to flow through pipe 18 without initially using up all of the local supply of heated water.

This system locates local water heater 100 disposed close to faucet 16. Heater 100 can be located in a cabinet under faucet 16, in a wall near faucet 16, or under the floor near faucet 16. An exemplary configuration locates heater 100 in a cabinet under faucet 16 so that local supply of heated water is delivered readily because the outlet of heater 100 is close to faucet 16. Heater 100 uses an enlarged heater tube 102 that has an inner diameter that is at least twice the inner diameter of hot water supply pipe 18 and can be three to six times as large. In configurations wherein heater tube is not circular in cross section, the internal dimensions are larger than the internal dimensions of the hot water supply pipe 18 so the water volume per unit length is larger within the heater tube than the supply pipe. Heater tube 102 is eight to twenty-four inches long so that it will fit in most under sink cabinets. One version of heater tube 102 is formed with standard-size two inch chlorinated polyvinyl chloride (CPVC) pipe that is eighteen inches long with an inlet cap 104 disposed at one end and an outlet cap 106 disposed at the opposite end.

An electric resistance heating wire 110 is wrapped around heater tube 102 with its wires spaced as shown in FIGS. 2 and 3. Nichrome resistance heating wire at thirty-four gauge is an example of an electric resistance heating wire 110. A loop of about seventeen feet (about 34 total feet of wire) is wrapped around heater tube 102 to heat the water inside heater tube 102. Wire 110 can be wrapped directly against the outer surface of heater tube 102 or a layer of thin metal such as aluminum tape is disposed between wire 110 and the outer surface of heater tube 102. A thin layer of metal 112 insulation such as aluminum tape is disposed over wire 110. One or more layers of insulation 114 are disposed outwardly of metal 112. Insulation 114 is a fiber-based insulation material capable of withstanding high heat levels.

A thermostat (circle on wire in FIG. 2) is provided to read the temperature of the water, the wire, or the sidewall of heater tube. The data from the thermostat is used by a controller that regulates the electric power supplied to heating wire 110. Heating wire 110 can be powered by 110V or 220V and can include a plug for an outlet. A ground fault circuit interrupter can be provided as required.

As discussed above, heater 100 uses a bypass tube 120 that delivers water from hot water supply pipe 18 to the outlet of heater tube 102 so that the water is mixed and the user does not receive only the hot water from within heater tube 102. Mixing throttles 122 and 124 are disposed within the water tubes to control the mixing rate. Throttles 122 and 124 can be carried by tube 120 and heater tube 102, the the connectors, or by the T-junction. In combination with the water pressure, the openings in throttles 122 and 124 control the flow rates of the local supply of heated water from within heater tube 102 and the water from bypass tube 120. These openings are sized to provide water to faucet 16 at a comfortable temperature while using up the local supply of heated water from within heater tube 102 just as the hot water from tank 12 reaches heater tube 102. In one configuration, the opening in throttle 122 has a diameter that is double the diameter of the opening in throttle 124 such as a one-quarter inch opening in throttle 122 and a one-eighth inch opening in throttle 124. At times, the timing is not possible because of the space between tank 12 and heater tube 102. In these situations, mixing throttles are configured to maximize the length of time the local supply of heated water is delivered at a comfortable temperature as desired by the user. A higher selected comfortable temperature lessens the length of the delivery while a cooler selected comfortable temperature increases the length of time the comfortable water lasts. A delivery of warm water for greater than thirty seconds is desired.

FIG. 4 depicts another configuration of heater 200 that uses heater tube 102 and a throttled outlet 124 but without bypass tube. In this configuration, the user mixes the local supply of heated water from heater tube 102 with the cold water otherwise supplied to faucet 16. In this configuration, throttle 124 is sealed with rubber washers at the connection between the faucet hot water supply line and the outlet of heater 200. This makes changing throttle 124 out for another with a different flow rate relatively easy.

In both of the configurations depicts in FIGS. 2-4, the outlet of heater 100 and 200 is connected to the hot water supply line that is connected to faucet 16.

In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed. Moreover, the above description and attached illustrations are an example and the invention is not limited to the exact details shown or described. Throughout the description and claims of this specification the words “comprise” and “include” as well as variations of those words, such as “comprises,” “includes,” “comprising,” and “including” are not intended to exclude additives, components, integers, or steps. 

1. A system for delivering heated water to a faucet, the system comprising: a hot water supply pipe adapted to deliver water from a water heater tank; a water heater having an inlet connected to the hot water supply pipe and an outlet in fluid communication with a faucet; the water heater having a heater tube that receives the water from the hot water supply pipe; an electric resistance heat wire wrapped around the heater tube; and the heater tube having an internal diameter larger than an internal diameter of the hot water supply pipe.
 2. The system of claim 1, wherein the electric resistance heat wire is disposed on the outside of the heater tube and does not contact water in the heater tube.
 3. The system of claim 2, further comprising a thin layer of metal disposed over the electric resistance heat wire.
 4. The system of claim 3, further comprising insulation disposed over the thin layer of metal.
 5. The system of claim 4, wherein the insulation is fiber-based.
 6. The system of claim 2, further comprising a thin layer of metal disposed between the electric resistance heat wire and the outside of the heater tube.
 7. The system of claim 1, wherein further comprising a throttle disposed between the faucet and the heater tube.
 8. The system of claim 1, wherein the heater tube has an internal diameter that is at least twice the internal diameter of the hot water supply pipe.
 9. The system of claim 1, wherein the heater tube has an internal diameter that is three to six times as large as the internal diameter of the hot water supply pipe.
 10. The system of claim 9, wherein the heater tube has a length of eight to twenty-four inches.
 11. The system of claim 10, wherein the heater tube is made from chlorinated polyvinyl chloride pipe.
 12. The system of claim 11, wherein the pipe is two inch pipe.
 13. The system of claim 1, wherein the electric resistance heat wire is powered from a 100 V power supply.
 14. The system of claim 13, wherein the electric resistance heat wire includes a plug. 